The document WO 2004/030726 discloses a needle device comprising a housing, a base portion having a mounting surface adapted for application to the skin of a patient and a plurality of needles. Each needle comprises a distal pointed end adapted to penetrate the skin of a patient and each needle has a first position in which the distal end is retracted relative to the mounting surface and a second position in which the distal end projects from the mounting surface. A needle device according to this document being mounted on the patients has to have a height at least corresponding to the length of a needle as the needles before and after use are retracted in their full length perpendicular to the mounting surface, also the cannulas according to the shown embodiments have to be hard, self-penetrating cannulas provided with a side net opening. According to WO 2004/030726 the inserter parts are an integrated part of the device, it is not possible to separate the inserter from the parts to be inserted.
The document US2004/158207, FIGS. 13-18, discloses an inserter for insertion of a cannula part where the inserter is provided with an insertion needle. When the cannula part is attached to the inserter, the sterility of the subcutaneous part of the cannula part is compromised. Thus, insertion has to take place shortly after the cannula part has been exposed to the surroundings in order to avoid contamination of the cannula part.
The document WO 99/33504 discloses an inserter for insertion of an infusion part wherein the inserter is provided with a plunger and no insertion needle. The insertion needle is part of the infusion set and is removed from the infusion set after the set has been inserted and the inserter has been removed. As soon as the infusion set is placed in the inserter, the sterility of the subcutaneous part of the infusion set is compromised. Thus, insertion has to take place shortly after the cannula part has been exposed to the surroundings in order to avoid contamination of the cannula part.